Dental appliances, such as orthodontic retainers, dental aligners (such as Invisalign®, ClearCorrect™, and other brands), dentures, sleep apnea appliances, sports mouth guards, etc., are often worn anywhere from 30 minutes to 23 hours a day or longer and accumulate food particles, saliva, dead gingiva (skin), and other detritus. Over time (ranging from minutes to hours), the dental appliance begins to smell bad and discolor. Currently, oral appliance cleaners are designed for use outside the mouth and require the appliance—dentures, retainers, mouth guards, etc.—to be soaked in the cleaning solution and sometimes cleaned in a sonic or ultrasonic cleaning device. Within 20 minute of being returned to the mouth, however, the appliance becomes dirty or contaminated again with food debris and microorganisms. A need exists for an oral appliance cleaner that can be used on the go, throughout the day if necessary, without requiring the appliance wearer to keep the appliance out of his or her mouth during the cleaning process.